Electric-motor-driven jack



F, A. KIRSTATTER.

ELECTRIC MOTOR DRIVEN JACK.

APPLICATION FILED MAY 1?, 1920.

Patented Jan. 31- 1922.

UNITED STATES FRANK A. KIRSTATTER, OF CLEVELAND, OHIO.

EECTBIC-MOTOR-DRIVEN JACK.

Application filed May 12,

To allwlwm it may concern:

Be it known that I, FRANK A. KIRSTATIER, a citizen of the United States, resident of Cleveland, county of Cuyahoga, and State of Ohio, have invented new and useful Improvements in Electric-Motor-Driven Jacks, of which the following is a specification, the principle of the invention being herein explained and the best mode in which I have 10 contemplated applying that principle, so as to distinguish it from other inventions.

My invention relates to jacks, and partlcularly to apparatus of this character adapted to be driven by an electric motor. The ob- 15 ject of the invention is to design a jack 2 description set forth in detail certain means embodying my invention, the disclosed means, however,"constituting but one of the various mechanical forms in which the principle of the invention may be apphed.

In said annexed drawing: A

Figure 1 represents a front elevation of a my invention;

Figure 2 represents a central longitudinal,

section; and

Figures 3 and 4 represent, respectively, transverse sections taken in the planes indicated by the lines IIIIII and IV-IV,

Figure 2. v

I provide a suitable casing 1 for my 1m- 3 proved jack, interiorly of which, by means of the screws 2, is secured the field 3 of the motor; Oneend of the casing ,1 is formed into a contracted-portion 4, and the spaces within the portions 1 and 4 are separated by a web or partition 11. Top and bottom plates covering the ends of the casing. are

designated by the ordinals 5 and 6, the top plate being contracted into a neck portion 7 adapted to form a guide for the longitudinally-movable, exteriorly-threaded member or screw 8 having a key-way 35 ada-pted to co-operate with a key 36 secured in the cover plate 5 and the neck portion 7 thereof. Having a hearing at one end, by means of a trunnion portion 9, in the cover. plate 6, and

receiving the screw 8, is a'tubular member 12 whose other end is secured by pins 12 to *a rotatable nut 13 journaled in the casing portion 4 adapted to co-operate with the screw 8. As shown, the tubular member 12 Specification of Letters Patent.

is secured to said nut 13 by means of a flange 12 and fitted intermediately this flange and the partition or web 11 in the casing 1 are suitable ball bearings and ball races 37.

. The rotating armature 14 of the motor is connected to the tubular member 12 so as to rotate the latter, and specifically this connection is afforded by the following detailed means: The armature 14 is secured to a second tubular member 17 surrounding the tubular member 12 and affording a bearing for the same; the armature 14 being confined between a ring 15 and a shoulder 16 formed in the exterior surface of said tubular member 17. The tubular member 17 is held to position longitudinally relatively to the armature 14 and connected. parts, by means of a nut 18 secured to the upper end thereof, as plainly shown in Figure 2, and bearing on the commutator segments 38 disposed between the ring 15 and the nut 18. Furthermore, the armature 14 and the tubular member 17 are secured together by a pin 41. Reduction gears 19, 20, 23 and 21 are provided for securing together the tubular shafts 17 and 12, the gears 19 and 20 being secured together by means of the pins 39, and the gears 20 and 23, and 19 and 21, respectively, intermeshing. The tubular member 17 is formed with a flange 17 and a pin 40 depends from this flange and rests upon the bottom plate 6. The two gears 19 and 20 rotate about this pin 40. For the purpose of vbettter balancing the structure, the gears 19 and 20 and the pins 40 are provided in oppositely disposed pairs, as shown. The gear 21 is secured to the tubular member 17 by the pins 22. The gear 23 is secured to the casing cover 6 by the pin 42. The gear 20 is formed with a greater number of teeth than the gear 19; the gear 21 with a greater number than thegear 19; and the gear 23 with a greater number than the gear 20. By this construction, the rotation of the armature 14 effects the rotation of the nut 13 at a reduced speed, which eflects the longitudinal movement of the screw 8, inasmuch as the latter cannot rotate because of the key 36 and key-way 35. The outward movement of the screw 8 will effect the raising of the load, a base or platform for the load being indicated by the member 10 secured to the upper end of the screw 8. I'al so provide means whereby the motor may be thrown on or ofli' by a limit switch at predetermined and desired positions of the spindle 8. The detail of this mechanism consists in providing a tubular extension 7 covered by a ca holes in the neck portion 7, said pins being adapted to project into the key-way 35. This key-way has a differential in its depth, the greater and intermediate, part of the latter being deeper than the ends 35, as indicatedby the ordinal 34, Figure 2. Adapted to contact with one end of, these pins 31 are a pair of insulating pins 30 projecting into an insulating member 32 into which projects the ends of a pair of copper contacts I 29, whose heads are adapted to bear against a co per plate 33. Aline 43 from the motor tot 0 switch is run through the conduit 28. It is evident that, in the position shown in Figure 2, the inward movement of the screw by 8 has resulted in the upper pin 31 being vforced outwardly by reason of contacting the lower end 35 ofthe key-way, to break with one of the shallow ends 35 of the keythe circuit and stop What I claim is:

1. In an electric-motor-driven jack, the combination of a longitudinally-movable screw-member; a casing; a top plate for the casing sion; rotata le means fitted within the casing the motor.

having a screw-threaded portion adapted to cooperate with said screw-member; means for preventing the rotation of said screw-. member; a motor mounted within said casing; means for connecting the armature of said motor to the screw-threaded. means to rotate the latter; and means disposed within said tubular extension whereby the motor may be thrown on and ofi.

2. In an electric-motor-driven jack, the combination of a, longitudinally-movable screw-member; a casing; rotatable means longitudinally fixed within said casing havmg a screw-threaded portion adapted to cooperate with said screw-member; means for preventing the rotation of said member; a tubular member rotatably mounted in saidcasing; a motor mounted withinsaid casing whose armature is' fixed to said tubular member, a second rotatable tubular member mounted within the bearing formed by said first tubular member; means for con- 7 for the neck 7 of the I cover plate 5, within which playa couplet of reciprocable pins 31 through suitable rovided with a tubular extennectin said second tubular member to the 'rotata 1e means; and reduction gears for sc curing together the said tubular members.

3 11 an electric-motor-driven jack, the combination of a longtiudinally-movablc screw member; a casing; rotatable means fixed within the casing having a screwthreaded portion adapted to co-operate with said screw-member; a top plate for said casing having a tubular extension; means for preventing the rotation of said member; a

tubular member mounted in said casing; a motor mounted within the casing with its armature fixed to said tubular member; a

second tubular member rotatably mounted within the bearing formed by said first tubular member; means for connecting said second tubular member to the rotatable means; intermeshing reduction 7 gears for connecting said tubular members; and means disposed within .said tubular extension whereby and off. 1

4. In an electric motor-driven jack, the combination of a longitudinally-movable screw-member; a casing; a rotatable nut longitudinally fixed in 'said casing and adapted to co-operate with said screw-member; means within which said screw-member is guided; means for-preventing the rotation of said screw; a tubular member rotatably mounted in said casing; a motor mounted in said casing and whose armature is fixed to said tubular member; a rotatable member fixed to said nut and disposed interiorly of said first tubular member; and

co-operating reduction gears secured to said tubular member and said last-mentioned rotatable member. p

5. In an electric-motor-driven jack, the combination of a longitudinally-movable screw; a casing; a rotatable nut longitudithe motor maybe thrown on. y

nally fixed in said casing and adapted to co-operate with said screw; means within which said screw is guided; means for preventing the rotation of said screw; a tubular member rotatably mounted in said casing; a motor. mounted in said casing and whose armature. is fixed to said tubular member; a second tubular member fixed to said nut and disposed interiorly of said first tubular member, said screw being disposed interiorly of said tubular members; and cooperating reduction gears secured to said tubular members. i

.6. In an electric-motor-driven jack, the combination of a longitudinally-movable screw; a casing; rotatable means longitudinally fixed in said casing and having a screw-threaded portion adapted to co-operate with said screw; means within which said screw is guided and which has a key co-operating with a key-way formed in said screw; a motor. mounted in said casingwhose armatuie is connected tosaid screwthreaded means to rotate the latter; a switch adapted to throw said motor on and off and longitudinally movable pins secured in said casing and adapted to control said switch, said key-way having different depths and said pins disposed to project into said keywa -7. In an electric-motor-driven jack, the combination of a longitudinally-movable screw-member; a casing: rotatable means longitudinally fixed in said casing and having a screw-threaded portion adapted to cooperate with said screw-member; means within which said screw-member is guided and which has a key co-operating with a key-way formed in said screw-member; a motor mounted in said casing; a tubular member rotatably mounted in said casing, the armature of said motor being fixed to said tubular member; means connecting said member to said screw-threaded means to rotate the latter; a switch adapted to throw said motor on and off; and movable pins secured in said casing and adapted to control said switch. said key-way having different depths and said pins disposed to project into said key-way.

8. In an electrlc-motor-driven jack, the combinatlon of a longitudinallv-movable screw-member: a casing: rotatable means longitudinally fixed in said casing and having a screw-threaded portion adapted to cooperate with said screw-member; means within which said screw-member is guided; means for preventing the rotation of said screw-member; a motor mounted in said casing; a journal member secured to the armature of said motor; a pair of gears secured together and adapted to rotate upon said journal member: a gear secured to said screw-threaded means, meshing with one of said pair of gears; and a fixed member having teeth meshing with the other of said pair of gears.

9. In an electric-motor-driven jack, the combination of a longitudinally-movable screw-member; a casing; a rotatable nut longitudinally fixed in said casing and adapted to co-operate with said screw-member; means within which said screw-member is guided; means for preventing the rotation of said screw; a tubular member rotatably mounted in said casing; amotor mounted in said casing and whose armature is fixed to said tubular member; a pin secured to said tubular member; a pair of gears having difierent numbers of teeth, secured together. and adapted to rotate upon said pin; a gear secured to said nut, and meshing with said smaller gear: and a gear having teeth greater in number than the other of said pair of gears, meshing with said gear. and fixed to said casing.

Signed by me this 7th da) of May, 1920.

F RANK A. KIR-STATTER. 

